If you're web app is menu focused with a lot of menu clicks/actions I would make it stick to the screens corner. If you've got a more story oriented app where the user reads the entire screen and then clicks next/previous it can stay at its place.
–
BarfieldmvJun 5 '12 at 6:32

Does this question give you the answers you need, or is your question requesting something not covered there?
–
JonW♦Jun 5 '12 at 8:45

+1 But it is possible to have content floating around a fixed position menu section with CSS.
–
Benny Skogberg♦Jun 5 '12 at 19:49

@BennySkogberg thanks Benny. yea I was thinking of that as well but I thought that it would be an odd design to do so. On the top of my head I can't think of any instance that adopts that kind of layout. maybe you can?
–
AndroidHustleJun 6 '12 at 16:12

No not really. Not even if you have a small 3.7" screen that design wouldn't do. This kind of technique was mainly used to float a mid-section fixed image for design reason only. "Look what we can do here" as web developers said in 1998 :-)
–
Benny Skogberg♦Jun 6 '12 at 16:55

Surely - as a user I never like sites where one has to scroll to the top just for a click to be taken to the next page. Of course the content of the site is important, but if the user is not looking for the content on the page, that page irritates him and he would not walk an extra mile in finding the right page on that site and instead move on.

In the case of lengthy content, another idea - if considerable in your case - could be a side panel which expands on click. This would give you ample space on the screen for the content and at the same time the user would have the menu available at anytime.

I like your idea of the side panel that expands on click. I am not sure about the first part of your answer as it is purely based on opinion and not answering the initial question, but I understand you are giving some context on the suggestion.
–
AdriaanJun 5 '12 at 19:20

Depends on the usefulness of the menu. If it's extremely likely to be used frequently, yes definitely good UX. However you have to consider the size of the menu vs total screen real-estate. If you are targeting a mobile device, or small screens and your menu bar is too big, the loss of screen real estate may out-weight the convenience of the menu's persistence.

Rule of thumb is that the top 18% of controls should be maximally accesible, but again, are you willing to sacrifice the space?

I think your targeted device are desktop & laptop with resolution more than 1024 by 768. Keeping menu fixed is a good option but, for future you should add a scrollbar to menu(as nowadays done by most of ipad apps. e.g: Facebook app). So that if in future number of links increase it will not be a problem for you. According to me you should be ready for future changes & enhancement to be done.